21349140 has 24 divisors (see below), whose sum is σ = 59777760. Its totient is φ = 5693088.

The previous prime is 21349117. The next prime is 21349183. The reversal of 21349140 is 4194312.

It is a self number, because there is not a number n which added to its sum of digits gives 21349140.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 177850 + ... + 177969.

It is an arithmetic number, because the mean of its divisors is an integer number (2490740).

Almost surely, 2^21349140 is an apocalyptic number.

21349140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21349140 is an abundant number, since it is smaller than the sum of its proper divisors (38428620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21349140 is a wasteful number, since it uses less digits than its factorization.

21349140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355831 (or 355829 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21349140 is about 4620.5129585361. The cubic root of 21349140 is about 277.4129911455.

It can be divided in two parts, 213491 and 40, that added together give a triangular number (213531 = T₆₅₃).

The spelling of 21349140 in words is "twenty-one million, three hundred forty-nine thousand, one hundred forty".